6. Delays. A user in Madagascar, connected to the internet via a 100 Mb/s (b-bits) connection retrieves a 250 KB (B-bytes) web page from a server in Tokyo, where the page references three images of 500 KB each. Assume that the one-way propagation delay is 82 ms and that the user's access link is the bandwidth bottleneck for this connection. a. Approximately how long does it take for the page (including images) to appear on the user's screen, assuming non-persistent HTTP using a single connection at a time? (For this part, you should ignore queueing delay and transmission delays at other links in the network) b. How long does it take if the connection uses persistent HTTP (single connection)? c. Suppose that user's access router has a 4 MB buffer (B-byte) on the link from the router to the user. How much delay does this buffer add during periods when the buffer is full?

6. Delays. A user in Madagascar, connected to the internet via a 100 Mb/s (b-bits) connection retrieves a 250 KB (B-bytes) web page from a server in Tokyo, where the page references three images of 500 KB each. Assume that the one-way propagation delay is 82 ms and that the user's access link is the bandwidth bottleneck for this connection. a. Approximately how long does it take for the page (including images) to appear on the user's screen, assuming non-persistent HTTP using a single connection at a time? (For this part, you should ignore queueing delay and transmission delays at other links in the network) b. How long does it take if the connection uses persistent HTTP (single connection)? c. Suppose that user's access router has a 4 MB buffer (B-byte) on the link from the router to the user. How much delay does this buffer add during periods when the buffer is full?

Operations Research : Applications and Algorithms

4th Edition

ISBN:9780534380588

Author:Wayne L. Winston

Publisher:Wayne L. Winston

Chapter20: Queuing Theory

Section20.10: Exponential Queues In Series And Open Queuing Networks

Problem 8P

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This elementary problem begins to explore propagation delay and transmission delay, two central concepts in datanetworking. Consider two hosts, A and B, connected by a single link of rate R bps. Suppose that the two hosts areseparated by m meters, and suppose the propagation speed along the link is s meters/sec. Host A is to send a packet ofsize L bits to Host B.a. Express the propagation delay, dprop, in terms of m and s.b. Determine the transmission time of the packet, dtrans, in terms of L and R.c. Ignoring processing and queuing delays, obtain an expression for the end-to-end delay.d. Suppose Host Abegins to transmit the packet at time t = 0. At time t = dtrans, where is the last bit of the packet?e. Suppose dprop is greater than dtrans. At time t = dtrans, where is the first bit of the packet?f. Suppose dprop is less than dtrans. At time t = dtrans, where is the first bit of the packet?g. g. Suppose s = 2.5 · 108, L = 120 bits, and R = 56 kbps. Find the distance m so that dprop…
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